For me regional competition is a completely different story.
The top tier competition should be "open" for all the teams in top domestic/regional competition. But the criteria has to be sport - not brand name.
When a regional competition is introduced then the domestic competition will probably be relegated to second tier. Its true what you are saying, not a lot of domestic competition in smaller leagues. Its the same story as in top football, the most money in a single country goes into top team or teo and then that makes the devastating pyramid and kills competition. The regional league could disperse that and give more competition and better distribution of money. But, as everything it should be an open league - you could be relegated and a team from domestic competition could be promoted. If that is not the case, then I am against it. And yes security risk is still a huge factor, that can not be overlooked.
Proud supporter of Deportivo la Coruna and Slovenia national football team